ass Solution {
public:
    int minPathSum(vector<vector<int>>& grid) {
        int m = grid.size(), n = grid[0].size();
        for (int i = 1; i < grid.size(); i++) grid[i][0] += grid[i - 1][0];
        for (int i = 1; i < grid[0].size(); i++) grid[0][i] += grid[0][i - 1];

        for (int i = 1; i < grid.size(); i++) {
            for (int j = 1; j < grid[0].size(); j++) {
                grid[i][j] = min(grid[i - 1][j], grid[i][j - 1]) + grid[i][j];
            }
        }
        return grid[m - 1][n - 1];
    }
};
